Metabolic engineering of Clostridium acetobutylicum for the enhanced production of isopropanol‐butanol‐ethanol fuel mixture. (18th April 2013)

• Record Type: Journal Article
• Authors: Jang, Yu‐Sin; Malaviya, Alok; Lee, Joungmin; Im, Jung Ae; Lee, Sang Yup; Lee, Julia; Eom, Moon‐Ho; Cho, Jung‐Hee; Seung, Do Young
• Is Part Of: Biotechnology progress. Volume 29:Number 4(2013:Jul./Aug.)
• Page Start: 1083
• Page End: 1088
• Publication Date: 2013-04-18
• Subjects: Biotechnology -- Periodicals; Food industry and trade -- Periodicals; Bioengineering -- Periodicals; 660.6
• DOI: 10.1002/btpr.1733
• Languages: English
• ISSNs: 8756-7938

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Butanol is considered as a superior biofuel, which is conventionally produced by clostridial acetone‐butanol‐ethanol (ABE) fermentation. Among ABE, only butanol and ethanol can be used as fuel alternatives. Coproduction of acetone thus causes lower yield of fuel alcohols. Thus, this study aimed at developing an improved <italic>Clostridium acetobutylicum</italic> strain possessing enhanced fuel alcohol production capability. For this, we previously developed a hyper ABE producing BKM19 strain was further engineered to convert acetone into isopropanol. The BKM19 strain was transformed with the plasmid pIPA100 containing the <italic>sadh</italic> (primary/secondary alcohol dehydrogenase) and <italic>hydG</italic> (putative electron transfer protein) genes from the <italic>Clostridium beijerinckii</italic> NRRL B593 cloned under the control of the thiolase promoter. The resulting BKM19 (pIPA100) strain produced 27.9 g/l isopropanol‐butanol‐ethanol (IBE) as a fuel alcohols with negligible amount of acetone (0.4 g/l) from 97.8 g/l glucose in lab‐scale (2 l) batch fermentation. Thus, this metabolically engineered strain was able to produce 99% of total solvent produced as fuel alcohols. The scalability and stability of BKM19 (pIPA100) were evaluated at 200 l pilot‐scale fermentation, which showed that the fuel alcohol yield could be improved to 0.37 g/g as compared to 0.29 g/g obtained at lab‐scale fermentation, while attaining a similar titer. To the best of our knowledge, this is the highest titer of IBE achieved and the first report on the large scale fermentation of <italic>C. acetobutylicum</italic> for IBE production. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1083–1088, 2013</p> </abstract>